Organische Phosphorverbindungen 42. Einige Reaktionen von Bis‐(dialkoxyphosphonyl‐methyl)‐O‐alkylphosphinaten und Tris‐(dialkoxyphosphonyl‐methyl)‐phosphinoxiden [1]

The metallation of alkyl bis‐(dialkyloxyphosphonyl‐methyl)‐phosphinates (I) and tris‐(dialkyloxyphosphonyl‐methyl)‐phosphine oxides (II) proceeds quantitatively with Na, K, or NaH in inert organic solvents. Alkylation of these metallated derivatives is effected with alkyl halides. In addition to the mono‐alkylated products, the di‐alkylated and the non‐alkylated products are formed also. The ester groups of II can be replaced by aryl groups by reaction with Grignard reagents to produce the corresponding tetratertiary phosphine oxides. Reduction of II with LiAlH 4 results in complete rupture of the molecule and produces only the cleavage products PH 3 and CH 3 PH 2 . Chlorination of the ester groups of I and II does not lead to uniform products. Concomitant with the chlorination of the ester groups, a cleavage reaction has been observed which produces as the main product Cl 2 CHP(O)Cl 2 . The anhydride of the hexa‐acid of II is readily obtained either by reaction of this acid with (CH 3 CO) 2 O or by reaction of II with (PhCO) 2 O. The titration behaviour and the high m. p. indicate an adamantane‐like structure for the anhydride. Halogenation of the bridging PCH 2 P groups of I and II is achieved by reaction with aqueous alkaline hypohalite at ambient temperature. This halogenation is accompanied by partial cleavage, and analytically pure samples could not be isolated.